Access Road Reinforcement For Mineral Sands Mine

Access road reinforcement with Neoloy® Geocells allowed weak soil to sustain heavy loads reaching high quality mineral sands

Challenge

High-quality deposits of zircon and other rare materials can be found in the sands of Tormin beach in the West Cape of South Africa. However, extracting them presented a world-class challenge, as the Mineral Commodities’ (MRC) heavy equipment necessary must traverse especially soft sand dunes, with extremely poor bearing capacity.

A reliable access road was required, which can sustain heavy loads over weak soil with minimal long-term deformation. It is the exact task for which geocells were created. In conjunction with the Obsideo Consulting firm and KayTec (the authorized distributor for South Africa), MRC decided that reinforcement through Neoloy Geocells would significantly increase strength and stiffness to make this possible.

Conventional Solution

Conventional solutions such as large-scale mats are impractical. They are heavy and unwieldly, typically requiring significant manpower and complex machinery to install. In addition, they need frequent and expensive maintenance, adding to the high cost. Mats are at best a temporary solution.

Neoloy Geocells Solution

Neoloy Geocells was clearly the best available solution. A single layer of 200mm high Neoloy Geocell was laid on top of Rockgrid PC 50/50 composite geotextile. It was then filled with graded stone crusher dust. 50 mm of compacted overfill was added as the surface layer.

The Neoloy geocells create a ‘beam effect’, acting as a semi-rigid mattress over the soft sand subgrade increasing its bearing capacity. As a result, after a year of transporting heavy equipment and regular operations traffic, the sand road has maintained integrity, displaying remarkable stability and showing little sign of degradation.

 

Benefits

Sustainable – used local infill; removable after mining ends

Fast, simple installation – 10 weeks to install 26,000 sq. m of pavement

Improves modulus of infill – increased layer modulus and strength

Stronger pavement – 3D “mattress” stabilized extreme subgrade conditions

Utilize local labor – on-site training and employment of local laborers

Testimonial – additional PRS-Neoloy reinforced roads have been requested by the client